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Discussion Starter #1
Just installed a new set of fuel pumps to replace the AEM pumps that I've been running for a few years and am curious to know if those running this setup with the new FPR have noticed a difference in fuel pressure.

Reason I ask is because after installation, I checked fuel pressure on the scanner and saw 107psi at idle where previously it was 70. After warm up it was 100psi. I haven't made any tune adjustments yet but did take it for a short spin to see if the low fuel pressure problem was fixed and it is.

It was difficult to keep an eye on the road and the laptop so I wasn't able to see what the pressure dropped to during WOT but it pulled great to redline on 3 separate pulls but my laptop battery died before I was able to make it back to the shop to save the log file.

Just seems a bit extreme that the FPR made a 30psi difference. Anyone else see similar results?

I'll charge the laptop this evening and get a few good pulls in the morning when it's a bit cooler to see how it's behaving.
 

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I have now heard of multiple people with 100+ cranking pressure with the DW FPR.

If you are still running returnless, you should not be seeing more than commanded pressure though. And 70 commanded at idle is high.
 

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Discussion Starter #3
I'll take a look at the tune tomorrow. Been running this same tune from Pat since April 2019.
 

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Discussion Starter #4
Desired fuel pressure was set to 448 for normal, high flow, low flow and cold engine. Adjusting them back to stock made no difference in fuel pressure - it idles at 102psi after warmup and runs at the same psi during normal driving. On a long 3rd to 4th gear pull, it drops to 73psi at 6800rpm.

Looking through the tune and comparing it to my stock file, I see that the FPCM Fitted under the Fuel System>General tab is set to NO where the stock tune has it set to YES.
 

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Discussion Starter #5
Pat sent a quick tune revision which fixed it.
 

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lol dang...how you were running around like that is a mystery. Yea you dont wanna turn off the fscm if you have one! Interesting stuff
 

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Discussion Starter #7 (Edited)
Definitely crazy and I'd been running like that for 16 months. His revision changed the NO to YES in the FSCM and changed a few pressure settings.

Took it for a short spin and it held 85psi to redline through a 2nd to 4th gear pull. I'm currently only at 23% ethanol so I'll have to see how it reacts when I go back to 50%.
 

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Definitely crazy and I'd been running like that for 16 months. His revision changed the NO to YES in the FSCM and changed a few pressure settings.

Took it for a short spin and it held 85psi to redline through a 2nd to 4th gear pull. I'm currently only at 23% ethanol so I'll have to see how it reacts when I go back to 50%.
I am having the same issue after going from the AEM pumps to the DW300c pumps. Seeing 97 PSI at startup and 105PSI under some boost. I need to get my tuned fixed also. With that high of fuel pressure its probably running a bit rich now.
 

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Discussion Starter #9
Pat G made a couple adjustments to my tune to fix it but I don't recall which areas he tweaked. I could run a comparison to find out.
 

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If its not to much trouble that would be great. I could get it turned down a bit before getting it tuned again. It makes me a bit nervous seeing almost 110psi.
 

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Discussion Starter #11
I'll check when I get to the shop tomorrow.
 

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Discussion Starter #13
PM sent
 
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